Electron Microscopic features of Organelle or Inclusion Flashcards
Surrounded by two membranes (nuclear
envelope) containing nuclear pore
complexes and perinuclear cisternal space
Regions with condensed and diffused chromatin
pattern (heterochromatin and euchromatin)
Nucleus
Dense, nonmembranous structure containing
fibrillar and granular material
Nucleolus
External membrane and membranes surrounding membranous organelles of cell; two inner and outer electron-dense layers separated by intermediate electron-lucent layer
Plasma membrane
Flattened sheets, sacs, and tubes of
membranes with attached ribosomes
rER
Flattened sheets, sacs, and tubes of
membranes without attached ribosomes
sER
Stack of flattened membrane sheets, often
adjacent to one side of nucleus
Golgi apparatus
Many relatively small, membrane-bounded
vesicles of uniform diameter, often polarized
on one side of cell
Secretory vesicles
Two-membrane system: outer membrane
and inner membrane arranged in numerous
folds (cristae)
In steroid-producing cells, inner membrane
arranged in tubular cristae
Mitochondria
Tubulovesicular structures with subdivided
lumen containing electron-lucent material or
other smaller vesicles
Endosomes
Membrane-bounded vesicles, often electron
dense
Lysosomes
Membrane-bounded vesicles, often with
electron-dense crystalloid inclusions
Peroxisomes
Long, linear staining pattern with width and
features characteristic of each fi lament type
Cytoskeletal elements
Minute dark dots, often associated with the rER
Ribosomes
Difficult to distinguish from other matrix proteins
Proteasomes
Nonmembranous, extremely dense grape-like
inclusions
Glycogen
